chore: add usage tracking package (#19095)

Not used in coderd yet, see stack.

Adds two new packages:
- `coderd/usage`: provides an interface for the "Collector" as well as a stub implementation for AGPL
- `enterprise/coderd/usage`: provides an interface for the "Publisher" as well as a Tallyman implementation

Relates to https://github.com/coder/internal/issues/814

coderd/database/migrations/testdata/fixtures/000359_create_usage_events_table.up.sql

@@ -0,0 +1,60 @@
+INSERT INTO usage_events (
+    id,
+    event_type,
+    event_data,
+    created_at,
+    publish_started_at,
+    published_at,
+    failure_message
+)
+VALUES
+-- Unpublished dc_managed_agents_v1 event.
+(
+    'event1',
+    'dc_managed_agents_v1',
+    '{"count":1}',
+    '2023-01-01 00:00:00+00',
+    NULL,
+    NULL,
+    NULL
+),
+-- Successfully published dc_managed_agents_v1 event.
+(
+    'event2',
+    'dc_managed_agents_v1',
+    '{"count":2}',
+    '2023-01-01 00:00:00+00',
+    NULL,
+    '2023-01-01 00:00:02+00',
+    NULL
+),
+-- Publish in progress dc_managed_agents_v1 event.
+(
+    'event3',
+    'dc_managed_agents_v1',
+    '{"count":3}',
+    '2023-01-01 00:00:00+00',
+    '2023-01-01 00:00:01+00',
+    NULL,
+    NULL
+),
+-- Temporarily failed to publish dc_managed_agents_v1 event.
+(
+    'event4',
+    'dc_managed_agents_v1',
+    '{"count":4}',
+    '2023-01-01 00:00:00+00',
+    NULL,
+    NULL,
+    'publish failed temporarily'
+),
+-- Permanently failed to publish dc_managed_agents_v1 event.
+(
+    'event5',
+    'dc_managed_agents_v1',
+    '{"count":5}',
+    '2023-01-01 00:00:00+00',
+    NULL,
+    '2023-01-01 00:00:02+00',
+    'publish failed permanently'
+)